There is a type of information input device that receives an operation input made by a user on an operation input device and performs various kinds of information processing. An information input device of this type obtains an input value that indicates the specifics of an operation input made by a user on an operation input device, and executes processing dictated by the input value, for example, moving a character or shifting a view point set within a virtual space. Concrete examples of the operation input include an operation in which the user touches a touch sensor with a finger, a stylus, or the like and an operation in which the user manipulates an operating member such as an analog stick. Some information input devices include, as an operation input device, a built-in sensor (e.g., a gyroscope) for detecting the tilt of a casing. When a user makes an operation that tilts the casing of this type of information input device, the information input device obtains as an input value a detection result value of the sensor which indicates the tilt, to thereby perform various kinds of information processing.